Nonionic surfactants based on polyoxyalkylene polyether derivatives are known in the art. These surfactants are used in cleaning compositions for cleaning hard surfaces, particularly for cleaning tableware and other utensils in machine dishwashers. The requirements for these nonionic surfactants are good cleaning, spotting and filming prevention, and good defoaming properties along with biodegradability.
In the U.S. Pat. No. 4,913,833 an automatic dishwashing detergent composition is disclosed comprising an active-chlorine compound and a sterically hindered epoxide-capped polyether polyol as a nonionic surfactant.
The U.S. Pat. No. 4,925,587 discloses specified derivatives of hydroxyalkyl polyalkylene glycol ethers for aqueous cleaning preparations for industrial and institutional purposes.
The U.S. Pat. No. 4,898,621 discloses a process of rinsing dishes and glassware in a dishwashing machine comprising a hydroxyalkyl polyethylene glycol ether. This patent is limited to the use of derivatives of polyethylene glycol ethers.
Some of these nonionic surfactants show improved results as foam-inhibiting agents but these properties are not fully sufficient for all cleaning applications.
Therefore, it was an object of the present invention to provide a nonionic surfactant for the use in cleaning compositions which show good cleaning properties, is low-foaming and in addition is biodegradable.